Re: [gobo-eiffel-develop] Bug in GEC ?

[Eric B. <er...@go...>]

Wolfgang Jansen wrote:
> Hmm, besides the definition of `$' there is another
> argument in favour of the address of the entity.
> If `$' yields the entity address then
> the object address can be obtained via C code
>    *(void**)addr

Not if the attribute is expanded.

> The other way around, obtaining the entity address
> from the object address is not possible.
> Thus, the entity address carries more information.

I think that we need both forms.

> The unreferencing might be done by a feature of TYPE,
> but how can the reverse operation be accomplished?
> I do not know ISE's INTERNAL class very well
> but I doubt that there is a function that yields
> the entity address of a given reference object:

I want the entity address of the attribute "foo"
in object `x':

    $x + internal.field_offset (i, x)

where `i' is the index of the attribute `foo' in `x'
(`i' can be computed by other means in INTERNAL).
I agree that it ought to be easier to get this information
(with less computation), but it is possible to get it.

Anyway, as Howard mentioned, the goal of Gobo is not to make
things better but to be compatible with ISE.

-- 
Eric Bezault
mailto:er...@go...
http://www.gobosoft.com